1
|
Derbikova KS, Levitsky SA, Chicherin IV, Vinogradova EN, Kamenski PA. Activation of Yeast Mitochondrial Translation: Who Is in Charge? BIOCHEMISTRY (MOSCOW) 2018; 83:87-97. [DOI: 10.1134/s0006297918020013] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
|
2
|
Ostojić J, Glatigny A, Herbert CJ, Dujardin G, Bonnefoy N. Does the study of genetic interactions help predict the function of mitochondrial proteins in Saccharomyces cerevisiae? Biochimie 2013; 100:27-37. [PMID: 24262604 DOI: 10.1016/j.biochi.2013.11.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2013] [Accepted: 11/06/2013] [Indexed: 10/26/2022]
Abstract
Mitochondria are complex organelles of eukaryotic cells that contain their own genome, encoding key subunits of the respiratory complexes. The successive steps of mitochondrial gene expression are intimately linked, and are under the control of a large number of nuclear genes encoding factors that are imported into mitochondria. Investigating the relationships between these genes and their interaction networks, and whether they reveal direct or indirect partners, can shed light on their role in mitochondrial biogenesis, as well as identify new actors in this process. These studies, mainly developed in yeasts, are significant because mammalian equivalents of such yeast genes are candidate genes in mitochondrial pathologies. In practice, studies of physical, chemical and genetic interactions can be undertaken. The search for genetic interactions, either aggravating or alleviating the phenotype of the starting mutants, has proved to be particularly powerful in yeast since even subtle changes in respiratory phenotypes can be screened in a very efficient way. In addition, several high throughput genetic approaches have recently been developed. In this review we analyze the genetic network of three genes involved in different steps of mitochondrial gene expression, from the transcription and translation of mitochondrial RNAs to the insertion of newly synthesized proteins into the inner mitochondrial membrane, and we examine their relevance to our understanding of mitochondrial biogenesis. We find that these genetic interactions are seldom redundant with physical interactions, and thus bring a considerable amount of original and significant information as well as open new areas of research.
Collapse
Affiliation(s)
- Jelena Ostojić
- Centre de Génétique Moléculaire, CNRS UPR3404 Associated to the University Paris XI-Sud, Avenue de la Terrasse, 91198 Gif-sur-Yvette Cedex, France
| | - Annie Glatigny
- Centre de Génétique Moléculaire, CNRS UPR3404 Associated to the University Paris XI-Sud, Avenue de la Terrasse, 91198 Gif-sur-Yvette Cedex, France
| | - Christopher J Herbert
- Centre de Génétique Moléculaire, CNRS UPR3404 Associated to the University Paris XI-Sud, Avenue de la Terrasse, 91198 Gif-sur-Yvette Cedex, France
| | - Geneviève Dujardin
- Centre de Génétique Moléculaire, CNRS UPR3404 Associated to the University Paris XI-Sud, Avenue de la Terrasse, 91198 Gif-sur-Yvette Cedex, France
| | - Nathalie Bonnefoy
- Centre de Génétique Moléculaire, CNRS UPR3404 Associated to the University Paris XI-Sud, Avenue de la Terrasse, 91198 Gif-sur-Yvette Cedex, France.
| |
Collapse
|
3
|
Perez-Martinez X, Broadley SA, Fox TD. Mss51p promotes mitochondrial Cox1p synthesis and interacts with newly synthesized Cox1p. EMBO J 2003; 22:5951-61. [PMID: 14592991 PMCID: PMC275423 DOI: 10.1093/emboj/cdg566] [Citation(s) in RCA: 153] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The post-transcriptional role of Mss51p in mitochondrial gene expression is of great interest since MSS51 mutations suppress the respiratory defect caused by shy1 mutations. SHY1 is a Saccharomyces cerevisiae homolog of human SURF1, which when mutated causes a cytochrome oxidase assembly defect. We found that MSS51 is required for expression of the mitochondrial reporter gene ARG8(m) when it is inserted at the COX1 locus, but not when it is at COX2 or COX3. Unlike the COX1 mRNA-specific translational activator PET309, MSS51 has at least two targets in COX1 mRNA. MSS51 acts in the untranslated regions of the COX1 mRNA, since it was required to synthesize Arg8p when ARG8(m) completely replaced the COX1 codons. MSS51 also acts on a target specified by the COX1 coding region, since it was required to translate either COX1 or COX1:: ARG8(m) coding sequences from an ectopic COX2 locus. Mss51p was found to interact physically with newly synthesized Cox1p, suggesting that it could coordinate Cox1p synthesis with insertion into the inner membrane or cytochrome oxidase assembly.
Collapse
Affiliation(s)
- Xochitl Perez-Martinez
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853-2703, USA
| | | | | |
Collapse
|
4
|
Barrientos A, Korr D, Tzagoloff A. Shy1p is necessary for full expression of mitochondrial COX1 in the yeast model of Leigh's syndrome. EMBO J 2002; 21:43-52. [PMID: 11782424 PMCID: PMC125806 DOI: 10.1093/emboj/21.1.43] [Citation(s) in RCA: 142] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
SHY1 codes for a mitochondrial protein required for full expression of cytochrome oxidase (COX) in Saccharomyces cerevisiae. Mutations in the homologous human gene (SURF1) have been reported to cause Leigh's syndrome, a neurological disease associated with COX deficiency. The function of Shy1p/Surf1p is poorly understood. Here we have characterized revertants of shy1 null mutants carrying extragenic nuclear suppressor mutations. The steady-state levels of COX in the revertants is increased by a factor of 4-5, accounting for their ability to respire and grow on non-fermentable carbon sources at nearly wild-type rates. The suppressor mutations are in MSS51, a gene previously implicated in processing and translation of the COX1 transcript for subunit 1 (Cox1) of COX. The function of Shy1p and the mechanism of suppression of shy1 mutants were examined by comparing the rates of synthesis and turnover of the mitochondrial translation products in wild-type, mutant and revertant cells. We propose that Shy1p promotes the formation of an assembly intermediate in which Cox1 is one of the partners.
Collapse
Affiliation(s)
| | | | - Alexander Tzagoloff
- Department of Biological Sciences, Columbia University, New York, NY 10027, USA
Corresponding author e-mail:
| |
Collapse
|
5
|
McIntyre P, Graf L, Mercer J, Peterson G, Hudson P, Hoogenraad N. A highly basic N-terminal extension of the mitochondrial matrix enzyme ornithine transcarbamylase from rat liver. FEBS Lett 2001; 177:41-6. [PMID: 6548714 DOI: 10.1016/0014-5793(84)80977-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
We have deduced the amino acid sequence of the N-terminal leader peptide of the mitochondrial enzyme ornithine transcarbamylase from a cDNA clone obtained from a rat liver cDNA library. The sequence is remarkable in being highly basic, having 4 arginine, 3 lysine and 1 histidine with no acidic residues in a total of 32 residues. The leader sequence has no extensive hydrophobic stretches, has 72% homology with the leader peptide of human ornithine transcarbamylase [1], and in terms of its basic character resembles the N-terminal extensions on a number of fungal mitochondrial [2-5] and pea chloroplast [6] proteins. Thus the basic nature of these leader peptides may constitute the signal for mitochondrial import.
Collapse
|
6
|
Simon M, Séraphin B, Faye G. The nuclear-encoded MSS2 gene is involved in the expression of the mitochondrial cytochrome-c oxidase subunit 2 (Cox2). BIOCHIMICA ET BIOPHYSICA ACTA 1995; 1228:95-8. [PMID: 7857963 DOI: 10.1016/0005-2728(94)00198-e] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Saccharomyces cerevisiae cells carrying the mss2-1 pet mutation contain no Cox2 protein (cytochrome-c oxidase subunit 2), through COX2 transcripts are synthesized and processed normally. Gene MSS2 was cloned and sequenced. It is localized on chromosome IV. The Mss2 protein does not show any significant homology with published sequences.
Collapse
Affiliation(s)
- M Simon
- Institut Curie-Biologie, Centre Universitaire, Orsay, France
| | | | | |
Collapse
|
7
|
Glerum DM, Tzagoloff A. Isolation of a human cDNA for heme A:farnesyltransferase by functional complementation of a yeast cox10 mutant. Proc Natl Acad Sci U S A 1994; 91:8452-6. [PMID: 8078902 PMCID: PMC44624 DOI: 10.1073/pnas.91.18.8452] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
We have cloned the human homolog of the Saccharomyces cerevisiae COX10 gene by functional complementation of a yeast cox10 null mutant. The 2.8-kb cDNA encoding the human heme A:farnesyltransferase codes for a 443-aa protein with high homology to the yeast and bacterial farnesylases. The human COX10 homolog, however, does not complement the mutation as efficiently as the yeast COX10 protein, likely due to the heterologous environment. PCR amplification and Southern analysis confirm the existence of a large mRNA for the human protein, with an unusually long 3' untranslated region. This clone can now be used to screen patients with inherited deficiencies in cytochrome oxidase in which the mutations remain unidentified and are likely to reside in a protein influencing the assembly of the enzyme.
Collapse
Affiliation(s)
- D M Glerum
- Department of Biological Sciences, Columbia University, New York, NY 10027
| | | |
Collapse
|
8
|
Dieckmann CL, Staples RR. Regulation of mitochondrial gene expression in Saccharomyces cerevisiae. INTERNATIONAL REVIEW OF CYTOLOGY 1994; 152:145-81. [PMID: 8206703 DOI: 10.1016/s0074-7696(08)62556-5] [Citation(s) in RCA: 72] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- C L Dieckmann
- Department of Biochemistry, University of Arizona, Tucson 85721
| | | |
Collapse
|
9
|
Affiliation(s)
- H J Pel
- Department of Molecular Cell Biology, University of Amsterdam, The Netherlands
| | | |
Collapse
|
10
|
Simon M, Della Seta F, Sor F, Faye G. Analysis of the MSS51 region on chromosome XII of Saccharomyces cerevisiae. Yeast 1992; 8:559-67. [PMID: 1523888 DOI: 10.1002/yea.320080707] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
We have localized gene MSS51 on chromosome XII of Saccharomyces cerevisiae between the RDN1 and CDC42 loci. 'Head to head' with MSS51 is another gene, QRI5, the function of which is unknown. However, the proximity of these genes, the structure of the intergenic region and the presence of an ABF1 binding site right in the middle of this region suggest that the MSS51 and QRI5 expressions are submitted to a common regulatory process.
Collapse
Affiliation(s)
- M Simon
- Institut Curie-Biologie, Orsay, France
| | | | | | | |
Collapse
|
11
|
|
12
|
Shan B, Vazquez E, Lewis JA. Interferon selectively inhibits the expression of mitochondrial genes: a novel pathway for interferon-mediated responses. EMBO J 1990; 9:4307-14. [PMID: 2176148 PMCID: PMC552214 DOI: 10.1002/j.1460-2075.1990.tb07879.x] [Citation(s) in RCA: 61] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
As an approach to identifying genes involved in physiological actions of interferons we used differential probes to screen a cDNA library from mouse L-929 cells treated with interferon alpha/beta. We identified two negatively regulated mRNA species which have been examined by analysis of the corresponding mRNAs and by DNA sequencing. Comparison with the GenBank database showed that these cDNA clones corresponded to mitochondrially encoded genes for cytochrome b and subunit I of cytochrome c oxidase. A further cDNA encompassing three mitochondrial genes was used as a probe to show that a third mRNA, NADH dehydrogenase subunit 5, was also down-regulated by interferon while a fourth, NADH dehydrogenase subunit 6, was unaffected. Expression of cytochrome b was also inhibited in mouse NIH 3T3 cells treated with interferon alpha/beta and in human Daudi lymphoblastoid cells treated with interferon alpha. The ability of interferon to reduce mitochondrial mRNA levels could be blocked by cycloheximide suggesting that these effects are mediated by an interferon-responsive nuclear gene which encodes a product capable of regulating mitochondrial gene expression. Analysis of proteins synthesized in the presence of emetine, a specific inhibitor of cytoplasmic translation, showed that the synthesis of several mitochondrial translation products, including cytochrome b, was reduced after treatment with interferon. Our results reveal a novel effect of interferon on cellular physiology which could have important consequences for understanding the effects of interferons as well as suggesting new mechanisms for the regulation of mitochondrial biogenesis and function.
Collapse
Affiliation(s)
- B Shan
- Department of Anatomy and Cell Biology, SUNY Health Science Center, Brooklyn 11203
| | | | | |
Collapse
|
13
|
Decoster E, Simon M, Hatat D, Faye G. The MSS51 gene product is required for the translation of the COX1 mRNA in yeast mitochondria. MOLECULAR & GENERAL GENETICS : MGG 1990; 224:111-8. [PMID: 2177521 DOI: 10.1007/bf00259457] [Citation(s) in RCA: 77] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The MSS51 gene product has been previously shown to be involved in the splicing of the mitochondrial pre-mRNA of cytochrome oxidase subunit I (COX1). We show here that it is specifically required for the translation of the COX1 mRNA. Furthermore, the paromocyin-resistance mutation (P454R) which affects the 15S mitoribosomal RNA, interferes, directly or indirectly, with the action of the MSS51 gene product. Possible roles of the MSS51 protein on the excision of COX1 introns are discussed.
Collapse
Affiliation(s)
- E Decoster
- Institut Curie, Section de Biologie, Orsay, France
| | | | | | | |
Collapse
|
14
|
Abstract
We describe a collection of nuclear respiratory-defective mutants (pet mutants) of Saccharomyces cerevisiae consisting of 215 complementation groups. This set of mutants probably represents a substantial fraction of the total genetic information of the nucleus required for the maintenance of functional mitochondria in S. cerevisiae. The biochemical lesions of mutants in approximately 50 complementation groups have been related to single enzymes or biosynthetic pathways, and the corresponding wild-type genes have been cloned and their structures have been determined. The genes defined by an additional 20 complementation groups were identified by allelism tests with mutants characterized in other laboratories. Mutants representative of the remaining complementation groups have been assigned to one of the following five phenotypic classes: (i) deficiency in cytochrome oxidase, (ii) deficiency in coenzyme QH2-cytochrome c reductase, (iii) deficiency in mitochondrial ATPase, (iv) absence of mitochondrial protein synthesis, and (v) normal composition of respiratory-chain complexes and of oligomycin-sensitive ATPase. In addition to the genes identified through biochemical and genetic analyses of the pet mutants, we have cataloged PET genes not matched to complementation groups in the mutant collection and other genes whose products function in the mitochondria but are not necessary for respiration. Together, this information provides an up-to-date list of the known genes coding for mitochondrial constituents and for proteins whose expression is vital for the respiratory competence of S. cerevisiae.
Collapse
Affiliation(s)
- A Tzagoloff
- Department of Biological Sciences, Columbia University, New York, New York 10027
| | | |
Collapse
|
15
|
Nobrega M, Nobrega F, Tzagoloff A. COX10 codes for a protein homologous to the ORF1 product of Paracoccus denitrificans and is required for the synthesis of yeast cytochrome oxidase. J Biol Chem 1990. [DOI: 10.1016/s0021-9258(18)77289-x] [Citation(s) in RCA: 60] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
|
16
|
Hartl FU, Pfanner N, Nicholson DW, Neupert W. Mitochondrial protein import. BIOCHIMICA ET BIOPHYSICA ACTA 1989; 988:1-45. [PMID: 2642391 DOI: 10.1016/0304-4157(89)90002-6] [Citation(s) in RCA: 531] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Most mitochondrial proteins are synthesized as precursor proteins on cytosolic polysomes and are subsequently imported into mitochondria. Many precursors carry amino-terminal presequences which contain information for their targeting to mitochondria. In several cases, targeting and sorting information is also contained in non-amino-terminal portions of the precursor protein. Nucleoside triphosphates are required to keep precursors in an import-competent (unfolded) conformation. The precursors bind to specific receptor proteins on the mitochondrial surface and interact with a general insertion protein (GIP) in the outer membrane. The initial interaction of the precursor with the inner membrane requires the mitochondrial membrane potential (delta psi) and occurs at contact sites between outer and inner membranes. Completion of translocation into the inner membrane or matrix is independent of delta psi. The presequences are cleaved off by the processing peptidase in the mitochondrial matrix. In several cases, a second proteolytic processing event is performed in either the matrix or in the intermembrane space. Other modifications can occur such as the addition of prosthetic groups (e.g., heme or Fe/S clusters). Some precursors of proteins of the intermembrane space or the outer surface of the inner membrane are retranslocated from the matrix space across the inner membrane to their functional destination ('conservative sorting'). Finally, many proteins are assembled in multi-subunit complexes. Exceptions to this general import pathway are known. Precursors of outer membrane proteins are transported directly into the outer membrane in a receptor-dependent manner. The precursor of cytochrome c is directly translocated across the outer membrane and thereby reaches the intermembrane space. In addition to the general sequence of events which occurs during mitochondrial protein import, current research focuses on the molecules themselves that are involved in these processes.
Collapse
Affiliation(s)
- F U Hartl
- Institut für Physiologische Chemie, Universität München, F.R.G
| | | | | | | |
Collapse
|
17
|
Hayasaka K, Brown GK, Danks DM, Droste M, Kadenbach B. Cytochrome c oxidase deficiency in subacute necrotizing encephalopathy (Leigh syndrome). J Inherit Metab Dis 1989; 12:247-56. [PMID: 2559245 DOI: 10.1007/bf01799214] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Tissues and cultured fibroblasts from two patients with Leigh syndrome (subacute necrotizing encephalopathy) were examined. A systemic defect in cytochrome oxidase was identified by enzyme assay and estimation of cytochrome concentrations. Immunochemical analysis showed a reduction of most subunits of the cytochrome oxidase complex. The rate of synthesis of cytochrome oxidase subunits, determined by labelling experiments in cultured fibroblasts, was the same in the patients and normal controls. The reduced cytochrome oxidase content of the patients' tissues must therefore result from abnormal turnover of the protein subunits.
Collapse
Affiliation(s)
- K Hayasaka
- Murdoch Institute for Research into Birth Defects, Royal Children's Hospital, Parkville, Melbourne, Victoria, Australia
| | | | | | | | | |
Collapse
|
18
|
Burke JM. Molecular genetics of group I introns: RNA structures and protein factors required for splicing--a review. Gene 1988; 73:273-94. [PMID: 3072260 DOI: 10.1016/0378-1119(88)90493-3] [Citation(s) in RCA: 148] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
In vivo and in vitro genetic techniques have been widely used to investigate the structure-function relationships and requirements for splicing of group-I introns. Analyses of group-I introns from extremely diverse genetic systems, including fungal mitochondria, protozoan nuclei, and bacteriophages, have yielded results which are complementary and highly consistent. In vivo genetic studies of fungal mitochondrial systems have served to identify cis-acting sequences within mitochondrial introns, and trans-acting protein products of mitochondrial and nuclear genes which are important for splicing, and to show that some mitochondrial introns are mobile genetic elements. In vitro genetic studies of the self-splicing intron within the Tetrahymena thermophila nuclear large ribosomal RNA precursor (Tetrahymena LSU intron) have been used to examine essential and nonessential RNA sequences and structures in RNA-catalyzed splicing. In vivo and in vitro genetic analysis of the intron within the bacteriophage T4 td gene has permitted the detailed examination of mutant phenotypes by analyzing splicing in vivo and self-splicing in vitro. The genetic studies combined with phylogenetic analysis of intron structure based on comparative nucleotide sequence data [Cech 73 (1988) 259-271] and with biochemical data obtained from in vitro splicing experiments have resulted in significant advances in understanding the biology and chemistry of group-I introns.
Collapse
Affiliation(s)
- J M Burke
- Department of Microbiology, University of Vermont, Burlington 05405
| |
Collapse
|
19
|
Michaelis U, Schlapp T, Rödel G. Yeast nuclear gene CBS2, required for translational activation of cytochrome b, encodes a basic protein of 45 kDa. MOLECULAR & GENERAL GENETICS : MGG 1988; 214:263-70. [PMID: 3070350 DOI: 10.1007/bf00337720] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
In yeast, synthesis of apocytochrome b from mitochondrial COB mRNA depends on at least three nuclear gene products. The translation stimulatory effect by two of these nuclear genes, CBS1 and CBS2, is mediated by the 5'-untranslated leader of COB mRNA. In this report, we show that CBS2 is located on chromosome IV and provide genetic evidence that the CBS2 gene encodes a polypeptide. Determination of the DNA sequence reveals a contiguous open reading frame of 1167 bp. The deduced polypeptide has a calculated molecular weight of 44.5 kDa and is characterized by a high content of positively charged amino acids. It has no significant homology to any known protein. The CBS2 gene is transcribed into low abundance mRNA species with a major transcription initiation site located 97 bp upstream from the ATG start codon next to a poly(dA-dT) stretch.
Collapse
Affiliation(s)
- U Michaelis
- Institut für Genetik und Mikrobiologie der Universität München, Federal Republic of Germany
| | | | | |
Collapse
|
20
|
Schulze M, Rödel G. SCO1, a yeast nuclear gene essential for accumulation of mitochondrial cytochrome c oxidase subunit II. MOLECULAR & GENERAL GENETICS : MGG 1988; 211:492-8. [PMID: 2835635 DOI: 10.1007/bf00425706] [Citation(s) in RCA: 98] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
We have identified and isolated a novel yeast nuclear gene (SCO1) which is essential for accumulation of the mitochondrially synthesized subunit II of cytochrome c oxidase (CoxII). Analysis of the mitochondrial translation products in a sco1-1 mutant reveals a strong reduction in CoxII. Examination of mitochondrial transcripts by Northern blot hybridization shows that transcription and transcript maturation of OXI1, the gene coding for CoxII, is not affected. Therefore the SCO1 gene product must be involved in a post-transcriptional step in the synthesis of CoxII. We have isolated a 1.7 kb DNA fragment from a yeast gene bank which carries the functional SCO1 gene. Two RNA species of 0.9 kb and 1.2 kb, respectively, hybridize with this DNA fragment, which is localized on chromosome II. Cells whose chromosomal 1.7 kb fragment has been replaced by the yeast URA3 gene fail to accumulate CoxII and in addition subunit I of cytochrome c oxidase (CoxI). The possibility that the SCO1 gene product is bifunctional, i.e. required for both CoxI and CoxII accumulation, is discussed.
Collapse
Affiliation(s)
- M Schulze
- Institut für Genetik und Mikrobiologie, Universität München, Federal Republic of Germany
| | | |
Collapse
|
21
|
Kloeckener-Gruissem B, McEwen JE, Poyton RO. Identification of a third nuclear protein-coding gene required specifically for posttranscriptional expression of the mitochondrial COX3 gene is Saccharomyces cerevisiae. J Bacteriol 1988; 170:1399-402. [PMID: 2830240 PMCID: PMC210925 DOI: 10.1128/jb.170.3.1399-1402.1988] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
A third nuclear protein-coding gene termed PET122 has been shown to be required for a post-transcriptional step in expression of the mitochondrial COX3 gene is Saccharomyces cerevisiae. pet122 mutants fail to produce cytochrome c oxidase subunit III, which is the polypeptide product of the COX3 gene, but produce normal amounts of mature COX3 mRNA. A strain bearing the pet122-1 allele is amber suppressible and correctly processes the 5' end of COX3 mRNA. Therefore, the PET122 gene product is a protein required for the expression of COX3 at some step after transcription and 5'-end processing of its transcript.
Collapse
Affiliation(s)
- B Kloeckener-Gruissem
- Department of Molecular, Cellular and Developmental Biology, University of Colorado, Boulder 80309-0347
| | | | | |
Collapse
|
22
|
Affiliation(s)
- L A Grivell
- Section for Molecular Biology, University of Amsterdam, The Netherlands
| |
Collapse
|
23
|
Saccharomyces cerevisiae positive regulatory gene PET111 encodes a mitochondrial protein that is translated from an mRNA with a long 5' leader. Mol Cell Biol 1987. [PMID: 2823103 DOI: 10.1128/mcb.7.8.2728] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The yeast nuclear gene PET111 is required specifically for translation of the mitochondrion-coded mRNA for cytochrome c oxidase subunit II. We have determined the nucleotide sequence of a 3-kilobase segment of DNA that carries PET111. The sequence contains a single long open reading frame that predicts a basic protein of 718 amino acids. The PET111 gene product is a mitochondrial protein, since a hybrid protein which includes the amino-terminal 154 amino acids of PET111 fused to beta-galactosidase is specifically associated with mitochondria. PET111 is translated from a 2.9-kilobase mRNA which, interestingly, has an extended 5'-leader sequence containing four short open reading frames upstream of the long open reading frame. These open reading frames exhibit an interesting pattern of overlap with each other and with the PET111 reading frame.
Collapse
|
24
|
Schmidt C, Söllner T, Schweyen RJ. Nuclear suppression of a mitochondrial RNA splice defect: nucleotide sequence and disruption of the MRS3 gene. MOLECULAR & GENERAL GENETICS : MGG 1987; 210:145-52. [PMID: 2448588 DOI: 10.1007/bf00337771] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
A mitochondrial RNA splice defect in the first intron of the COB gene (bI1) can be suppressed by a dominant nuclear mutation SUP-101. Starting with a gene bank of yeast nuclear DNA from a SUP-101 suppressor strain cloned in the YEp13 plasmid, we have isolated a recombinant plasmid which exerts a suppressor activity similar to the SUP-101 allele. The N3(2) insert of this plasmid contains an open reading frame (ORF) of 1014 bp which is transcribed to a 12 S RNA. Deletion of the 5' end of this ORF and its upstream sequences abolishes the suppressor activity. The N3(2) insert thus carries a functional gene (called MRS3) which can suppress a mitochondrial splice defect. The chromosomal equivalent of the cloned gene has been mapped to chromosome 10. Disruption of this chromosomal gene has no phenotypic effect on wild-type cells.
Collapse
Affiliation(s)
- C Schmidt
- Institut für Genetik und Mikrobiologie, Universität München, Federal Republic of Germany
| | | | | |
Collapse
|
25
|
Séraphin B, Boulet A, Simon M, Faye G. Construction of a yeast strain devoid of mitochondrial introns and its use to screen nuclear genes involved in mitochondrial splicing. Proc Natl Acad Sci U S A 1987; 84:6810-4. [PMID: 3309947 PMCID: PMC299174 DOI: 10.1073/pnas.84.19.6810] [Citation(s) in RCA: 99] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
We have constructed a respiring yeast strain devoid of mitochondrial introns to screen nuclear pet- mutants for those that play a direct role in mitochondrial intron excision. Intron-less mitochondria are introduced by cytoduction into pet- strains that have been made rho0; cytoductants therefrom recover respiratory competency if the original pet- mutation is required only for mitochondrial splicing. By this means, we have identified 11 complementation groups of such genes. Their total number may be estimated as about 18.
Collapse
Affiliation(s)
- B Séraphin
- Institut Curie, Centre Universitaire, Orsay, France
| | | | | | | |
Collapse
|
26
|
Kloeckener-Gruissem B, McEwen JE, Poyton RO. Nuclear functions required for cytochrome c oxidase biogenesis in Saccharomyces cerevisiae: multiple trans-acting nuclear genes exert specific effects on expression of each of the cytochrome c oxidase subunits encoded on mitochondrial DNA. Curr Genet 1987; 12:311-22. [PMID: 2833360 DOI: 10.1007/bf00405753] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Fourteen nuclear complementation groups of mutants that specifically affect the three mitochondrially-encoded subunits of yeast cytochrome c oxidase have been characterized. Genes represented by these complementation groups are not required for mitochondrial transcription, transcript processing, or translation per se but are required for the expression of one of the three genes--COX1, COX2, or COX3--which encode the cytochrome c oxicase subunits I, II, or III, respectively. Five of these genes affect the biogenesis of cytochrome c oxidase subunit I, 3 affect the biogenesis of subunit II, 3 affect the biogenesis of subunit III and 3 affect the biogenesis of both cytochrome c oxidase subunit I and cytochrome b, the product of COB. Among the 5 complementation groups of mutants that affect the expression of COX1, 2 lack COX1 transcripts, 1 produces incompletely processed COX1 transcripts, and 2 contain normal levels of normal-sized COX1 transcripts. In contrast, all 3 complementation groups which affect the expression of COX2 and all 3 complementation groups which affect the expression of COX3 exhibit no, or little, detectable difference with respect to the wild type pattern of transcripts. The 3 complementation groups which affect the expression of both COX1 and COB all have aberrant COX1 and COB transcript patterns. These findings indicate that multiple trans-acting nuclear genes are required for specific expression of each COX gene encoded on mitochondrial DNA and suggest that their products act at different steps in the expression of these mitochondrial genes.
Collapse
Affiliation(s)
- B Kloeckener-Gruissem
- Department of Molecular, Cellular and Developmental Biology, University of Colorado, Boulder 80309-0347
| | | | | |
Collapse
|
27
|
Strick CA, Fox TD. Saccharomyces cerevisiae positive regulatory gene PET111 encodes a mitochondrial protein that is translated from an mRNA with a long 5' leader. Mol Cell Biol 1987; 7:2728-34. [PMID: 2823103 PMCID: PMC367889 DOI: 10.1128/mcb.7.8.2728-2734.1987] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
The yeast nuclear gene PET111 is required specifically for translation of the mitochondrion-coded mRNA for cytochrome c oxidase subunit II. We have determined the nucleotide sequence of a 3-kilobase segment of DNA that carries PET111. The sequence contains a single long open reading frame that predicts a basic protein of 718 amino acids. The PET111 gene product is a mitochondrial protein, since a hybrid protein which includes the amino-terminal 154 amino acids of PET111 fused to beta-galactosidase is specifically associated with mitochondria. PET111 is translated from a 2.9-kilobase mRNA which, interestingly, has an extended 5'-leader sequence containing four short open reading frames upstream of the long open reading frame. These open reading frames exhibit an interesting pattern of overlap with each other and with the PET111 reading frame.
Collapse
Affiliation(s)
- C A Strick
- Section of Biochemistry, Molecular and Cell Biology, Cornell University, Ithaca, New York 14853
| | | |
Collapse
|
28
|
Séraphin B, Simon M, Faye G. The mitochondrial reading frame RF3 is a functional gene in Saccharomyces uvarum. J Biol Chem 1987. [DOI: 10.1016/s0021-9258(18)61090-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
|
29
|
Product of Saccharomyces cerevisiae nuclear gene PET494 activates translation of a specific mitochondrial mRNA. Mol Cell Biol 1987. [PMID: 3099165 DOI: 10.1128/mcb.6.11.3694] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
The product of Saccharomyces cerevisiae nuclear gene PET494 is known to be required for a posttranscriptional step in the accumulation of one mitochondrial gene product, subunit III of cytochrome c oxidase (coxIII). Here we show that the PET494 protein probably acts in mitochondria by demonstrating that both a PET494-beta-galactosidase fusion protein and unmodified PET494 are specifically associated with mitochondria. To define the PET494 site of action, we isolated mutations that suppress a pet494 deletion. These mutations were rearrangements of the mitochondrial gene oxi2 that encodes coxIII. The suppressor oxi2 genes had acquired the 5'-flanking sequences of other mitochondrial genes and gave rise to oxi2 transcripts carrying the 5'-untranslated leaders of their mRNAs. These results demonstrate that in wild-type cells PET494 specifically promotes coxIII translation, probably by interacting with the 5'-untranslated leader of the oxi2 mRNA.
Collapse
|
30
|
|
31
|
Kreike J, Schulze M, Pillar T, Körte A, Rödel G. Cloning of a nuclear gene MRS1 involved in the excision of a single group I intron (bI3) from the mitochondrial COB transcript in S. cerevisiae. Curr Genet 1986; 11:185-91. [PMID: 2834089 DOI: 10.1007/bf00420605] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The respiratory deficient yeast nuclear mutant MK3 is defective in the synthesis of the mature transcripts of the mitochondrial COB and OX13 genes, which code for apocytochrome b and subunit I of cytochrome c oxidase, resp. Introns 3 and 4 of the COB transcript (bI3 and bI4) and intron 4 (aI4) of the OXI3 transcript can not be excised (Pillar et al. 1983a, b). When combined with mitochondrial genomes lacking introns bI1, bI2 and bI3, or lacking intron bI3 alone the mutant is respiratory competent. Thus, the non-excision of bI4 and aI4 turns out to be an indirect effect of the mutation. From a wild type yeast genebank a plasmid has been isolated with a 3.3 kb DNA insert, which complements the mutant. Subcloning experiments assigned the functional gene to a 1.6 kb HaeIII-Sau3A fragment. Hybridization experiments showed, that it is (i) a single copy gene, (ii) also present in strain D273-10B, containing the "short form" mitochondrial genome (lacking the COB introns bI1-bI3), and (iii) located on chromosome IX. The nuclear gene defective in mutant MK3, was named MRS1 (Mitochondrial RNA Splicing). The involvement of this nuclear gene in the excision of a single group I mitochondrial intron (bI3) of the COB transcript is discussed.
Collapse
Affiliation(s)
- J Kreike
- Institut für Genetik und Mikrobiologie, Universität München, Federal Republic of Germany
| | | | | | | | | |
Collapse
|
32
|
Obaru K, Nomiyama H, Shimada K, Nagashima F, Morino Y. Cloning and sequence analysis of mRNA for mouse aspartate aminotransferase isoenzymes. J Biol Chem 1986. [DOI: 10.1016/s0021-9258(19)75987-0] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
|
33
|
Costanzo MC, Fox TD. Product of Saccharomyces cerevisiae nuclear gene PET494 activates translation of a specific mitochondrial mRNA. Mol Cell Biol 1986; 6:3694-703. [PMID: 3099165 PMCID: PMC367130 DOI: 10.1128/mcb.6.11.3694-3703.1986] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
The product of Saccharomyces cerevisiae nuclear gene PET494 is known to be required for a posttranscriptional step in the accumulation of one mitochondrial gene product, subunit III of cytochrome c oxidase (coxIII). Here we show that the PET494 protein probably acts in mitochondria by demonstrating that both a PET494-beta-galactosidase fusion protein and unmodified PET494 are specifically associated with mitochondria. To define the PET494 site of action, we isolated mutations that suppress a pet494 deletion. These mutations were rearrangements of the mitochondrial gene oxi2 that encodes coxIII. The suppressor oxi2 genes had acquired the 5'-flanking sequences of other mitochondrial genes and gave rise to oxi2 transcripts carrying the 5'-untranslated leaders of their mRNAs. These results demonstrate that in wild-type cells PET494 specifically promotes coxIII translation, probably by interacting with the 5'-untranslated leader of the oxi2 mRNA.
Collapse
|
34
|
Rödel G, Michaelis U, Forsbach V, Kreike J, Kaudewitz F. Molecular cloning of the yeast nuclear genes CBS1 and CBS2. Curr Genet 1986; 11:47-53. [PMID: 2834079 DOI: 10.1007/bf00389425] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The yeast nuclear genes CBS1 and CBS2 are both required for translation of the mitochondrial COB transcripts. Here we report on the identification of two unique chromosomal DNA-sequences of 2 kb and 2.3 kb from yeast wild type gene banks which functionally complement cbs1 and cbs2 mutants, respectively. Disruption of the homologous DNA-fragments by insertion of the URA3 gene generates respiratory deficient cells which fail to complement the original mutants. Cells with these gene disruptions are phenotypically identical to the original cbs1 and cbs2 mutants with respect to cytochrome spectra and mitochondrial translation products. The results exclude the possibility that suppressor genes have been cloned and confirm the conclusion that both genes, CBS1 and CBS2, specifically are involved in translation of mitochondrial COB RNA.
Collapse
Affiliation(s)
- G Rödel
- Institut für Genetik und Mikrobiologie der Universität München, Federal Republic of Germany
| | | | | | | | | |
Collapse
|
35
|
McEwen JE, Ko C, Kloeckner-Gruissem B, Poyton RO. Nuclear functions required for cytochrome c oxidase biogenesis in Saccharomyces cerevisiae. Characterization of mutants in 34 complementation groups. J Biol Chem 1986. [DOI: 10.1016/s0021-9258(18)67323-5] [Citation(s) in RCA: 124] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
|
36
|
Crochet J, Soret J, Perbal B. A cryptic transcription promoter in the myb oncogene of avian myeloblastosis virus. Virology 1986; 150:252-9. [PMID: 3006338 DOI: 10.1016/0042-6822(86)90284-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The potential regulatory signals contained in the v-myb oncogene of avian myeloblastosis virus have been inserted upstream to the herpes simplex type 1 thymidine kinase gene in order to test their promoter activity. The isolation of TK+ transformants after transfection of clone 1D(TK-) mouse cells with the resulting recombinant DNAs indicated that the expression of the TK gene was made possible by the myb-derived sequences. Analysis of the TK specific RNA expressed in different TK+ transformants revealed that the regulatory signals contained in v-myb correspond to a weak functional promoter.
Collapse
|
37
|
Costanzo MC, Mueller PP, Strick CA, Fox TD. Primary structure of wild-type and mutant alleles of the PET494 gene of Saccharomyces cerevisiae. MOLECULAR & GENERAL GENETICS : MGG 1986; 202:294-301. [PMID: 3010052 DOI: 10.1007/bf00331654] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The product of the yeast nuclear gene PET494 is required specifically for the translation of the mitochondrially encoded subunit III of cytochrome c oxidase. We have determined the DNA sequence of a 1.9 kb fragment carrying PET494. The sequence contains a single long open reading frame of 489 codons. This open reading frame encodes the PET494 protein since the DNA sequence of the corresponding fragment derived from a strain with a known pet494 amber mutation contained an in frame UAG codon. The results of S1 nuclease protection experiments demonstrated that this region is transcribed and that the 5' ends of the major transcripts lie 30 to 40 base-pairs upstream of the first AUG codon in the PET494 reading frame. The predicted PET494 protein has a highly basic amino-terminal domain of 66 amino acids followed by a stretch of 32 uncharged residues, half of which are hydrophobic. The remainder of the protein is not unusual in amino acid composition or distribution except that the carboxyterminal region is notably basic. The phenotype of mutations generated in vitro around codon 119 by exonuclease digestion and linker insertion indicated that this region is dispensable for function. A mutation caused by deletion of 101 bp of coding sequence behaved like a simple frameshift when inserted into the chromosome: it was partially suppressed by the recessive non-group specific frameshift suppressor suf13 and reverted to Pet+ phenotype by mutations linked to PET494.
Collapse
|
38
|
Fox TD. Nuclear gene products required for translation of specific mitochondrially coded mRNAs in yeast. Trends Genet 1986. [DOI: 10.1016/0168-9525(86)90192-7] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
|
39
|
Hanes SD, Koren R, Bostian KA. Control of cell growth and division in Saccharomyces cerevisiae. CRC CRITICAL REVIEWS IN BIOCHEMISTRY 1986; 21:153-223. [PMID: 3530635 DOI: 10.3109/10409238609113611] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Considerable advances have been made in recent years in our understanding of the biochemistry of protein and nucleic acid synthesis and, particularly, the molecular biology of gene expression in eukaryotes. The yeast Saccharomyces cerevisiae, and to a lesser extent Schizosaccharomyces pombe, has had a preeminent role as a focus for these studies, principally because of the facility with which these organisms can be experimentally manipulated biochemically and genetically. This review will be designed to critically examine and integrate recent advances in several vital areas of regulatory control of enzyme synthesis in yeast: structure and organization of DNA, transcriptional regulation, post-transcriptional modification, control of translation, post-translational modification and secretion, and cell-cycle modulation. It will attempt to emphasize and illustrate, where detailed information is available, principal underlying molecular mechanisms, and it will attempt to make relevant comparisons of this material to inferred and demonstrated facets of regulatory control of enzyme and protein synthesis in higher eukaryotes.
Collapse
|
40
|
Joh T, Nomiyama H, Maeda S, Shimada K, Morino Y. Cloning and sequence analysis of a cDNA encoding porcine mitochondrial aspartate aminotransferase precursor. Proc Natl Acad Sci U S A 1985; 82:6065-9. [PMID: 3862118 PMCID: PMC390700 DOI: 10.1073/pnas.82.18.6065] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
The primary structure of pig mitochondrial aspartate aminotransferase (mAspATase; L-aspartate:2-oxoglutarate aminotransferase, EC 2.6.1.1) precursor was deduced from its cDNA sequence. A library of cDNA clones was constructed from pig liver poly(A)+ RNA by applying the vector/primer method of Okayama and Berg [Okayama, H. & Berg, P. (1982) Mol. Cell. Biol. 2, 161-170]. The library was screened for pig mAspATase sequences by using a mixture of eight oligodeoxyribonucleotides as a probe. The sequences of the probe were deduced from the known amino acid sequence of pig mAspATase residues 196-201. Two recombinant plasmids containing inserts of about 2500 and 2600 base pairs were selected for sequence analysis. The amino acid sequence predicted from the cDNA sequence shows that the pig mAspATase precursor consists of the mature enzyme of 401 amino acid residues and an amino-terminal segment of 29 amino acid residues called the "presequence" that contains four basic amino acid residues, no acidic residues, and no hydrophobic amino acid stretch. The sequence of this 29-amino acid mAspATase precursor segment was compared with the presequences of other mitochondrial enzymes.
Collapse
|
41
|
Collins RA, Lambowitz AM. RNA splicing in Neurospora mitochondria. Defective splicing of mitochondrial mRNA precursors in the nuclear mutant cyt18-1. J Mol Biol 1985; 184:413-28. [PMID: 2413216 DOI: 10.1016/0022-2836(85)90291-8] [Citation(s) in RCA: 60] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
cyt18-1 (299-9) is a nuclear mutant of Neurospora crassa that has been shown to have a temperature-sensitive defect in splicing the mitochondrial large rRNA intron. In the present work, we investigate the effect of the cyt18-1 mutation on splicing of mitochondrial mRNA introns. Two genes were studied in detail; the cytochrome b (cob) gene, which contains two introns, and a "long form" of the cytochrome oxidase subunit I (coI) gene, which contains four introns. We found that splicing of both cob introns and splicing of at least two of the coI introns are strongly inhibited in the mutant, whereas splicing of coI intron 1, which is excised as a 2.6 X 10(3) base circle, is relatively unaffected. The rRNA intron and both cob introns are group I introns, whereas the circular coI intron may belong to another structural class. Control experiments showed that the degree of inhibition of splicing is greater in the mutant than can be accounted for by severe inhibition of mitochondrial protein synthesis. Finally, experiments in which mutant cells were shifted from 25 degrees C to 37 degrees C showed that splicing of the large rRNA precursor and splicing of the coI mRNA precursor are inhibited with similar kinetics. Considered together, our results suggest that the cyt18 gene encodes a trans-acting component that is required for the splicing of group I mitochondrial DNA introns or some subclass thereof. Since Neurospora cob intron 1 has been shown to be self-splicing in vitro, defective splicing of this intron in cyt18-1 indicates that an essentially RNA-catalyzed splicing reaction must be facilitated by a trans-acting factor, presumably a protein, in vivo.
Collapse
|
42
|
Séraphin B, Simon M, Faye G. Primary structure of a gene for subunit V of the cytochrome c oxidase from Saccharomyces cerevisiae. Curr Genet 1985; 9:435-9. [PMID: 2836092 DOI: 10.1007/bf00434047] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
We have isolated a gene coding for cytochrome c oxidase subunit V by genetic complementation in yeast. This protein is made as a 153 amino acid long precursor; its amino-terminal extension of 20 amino acids contains four basic residues and no acidic one, a feature common to most pre-sequences of imported mitochondrial proteins.
Collapse
Affiliation(s)
- B Séraphin
- Institut Curie, Section de Biologie, Orsay, France
| | | | | |
Collapse
|
43
|
Abstract
In the fungus Podospora, a correlation has recently been established between the presence of circular DNA molecules arising from the mitochondrial genome (SEN-DNAs) and the senescence syndrome. Here, I propose a hypothesis which accounts for the initial event which leads to the first SEN-DNA. A molecule in the most frequent situation where the SEN-DNA is an intron which might code for a maturase. This hypothesis is based upon several observations made either in Podospora or in the yeast S. cerevisiae. It assumes that mitochondrially synthesized maturases are unspecific nucleases able to work at the level of RNA and DNA molecules. Their specificity for RNA splicing instead of DNA is given by cytoplasmic proteins. Therefore, if the balance between cytoplasmic and mitochondrial protein syntheses is disturbed in favour of the mitochondrial compartment, the maturase would be accumulated and allowed to splice introns from DNA instead of RNA molecules. This hypothesis can account for aging of higher eucaryotic cells by postulating analogous processes in their nuclear compartment.
Collapse
|
44
|
Labouesse M, Dujardin G, Slonimski PP. The yeast nuclear gene NAM2 is essential for mitochondrial DNA integrity and can cure a mitochondrial RNA-maturase deficiency. Cell 1985; 41:133-43. [PMID: 2986842 DOI: 10.1016/0092-8674(85)90068-6] [Citation(s) in RCA: 55] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Dominant mutations in the yeast nuclear gene NAM2 cure the RNA splicing deficiency resulting from the inactivation of the bI4 maturase encoded by the fourth intron of the mitochondrial cytochrome b gene. This maturase is required to splice the fourth intron of this gene and to splice the fourth intron of the mitochondrial gene oxi3 encoding cytochrome oxidase subunit I. We have cloned the nuclear gene NAM2, which codes for two overlapping RNAs, 3.2 kb and 3.0 kb long, which are transcribed in the same direction but differ at their 5' ends. NAM2 compensating mutations probably result from point mutations in the structural gene. Integration of the cloned gene occurs at its homologous locus on the right arm of chromosome XII. Inactivation of the NAM2 gene either by transplacement with a deleted copy of the gene, or by disruption, is not lethal to the cell, but leads to the destruction of the mitochondrial genome with the production of 100% cytoplasmic petites.
Collapse
|
45
|
Séraphin B, Simon M, Faye G. A mitochondrial reading frame which may code for a maturase-like protein in Saccharomyces cerevisiae. Nucleic Acids Res 1985; 13:3005-14. [PMID: 2987871 PMCID: PMC341210 DOI: 10.1093/nar/13.8.3005] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
In S. cerevisiae, the large oxi3/oli2 mitochondrial transcript contains the products of the oxi3, aap1 and oli2 genes and an unassigned reading frame, RF3. In the work presented here, we have completed the nucleotide sequence of RF3. We have shown that RF3 is composed of four fairly large ORFs which overlap within GC rich sequences. Furthermore, a shift of +1 base was found between each pair of consecutive reading frames. We discuss how these frameshifts could be removed to produce a 500 aminoacid long protein containing the two well conserved P1 and P2 oligopeptide sequences featuring several mitochondrial intron reading frames, suggesting, thereby, a RNA-maturase-like activity for the putative RF3 protein. In addition, we suggest that the insertion of GC clusters in a gene could provide a novel way of regulating its expression.
Collapse
|
46
|
McIntyre P, Graf L, Mercer JF, Wake SA, Hudson P, Hoogenraad N. The primary structure of the imported mitochondrial protein, ornithine transcarbamylase from rat liver: mRNA levels during ontogeny. DNA (MARY ANN LIEBERT, INC.) 1985; 4:147-56. [PMID: 3838931 DOI: 10.1089/dna.1985.4.147] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Ornithine transcarbamylase, one of the enzymes of the urea cycle in ureotelic organisms, is synthesized in the cytoplasm of hepatocytes as a precursor larger than the mature form found in the mitochondrial matrix. We deduced the amino acid sequence of the precursor of ornithine transcarbamylase from rat liver from the nucleotide sequence of overlapping cDNA clones spanning the complete coding region, 3' untranslated region, and most of the 5' untranslated region of the mRNA. The mature enzyme consists of 322 amino acids and is derived from the larger precursor by proteolytic removal of 32 amino acids from the amino-terminus. The amino-terminal extension contains eight basic and no acidic residues. This highly basic character appears to be a feature of presequences on cytoplasmically synthesized mitochondrial proteins. Comparison of the amino acid sequence determined for the enzyme from rat with that from human liver (Horwich et al., 1984) shows that there is a high degree of homology between the sequences of the mature protein (93%) and relatively less homology between the sequences of the amino-terminal extension (72%). The ornithine transcarbamylase from rat liver also shows a considerable degree of amino acid homology (44%) with the enzyme from Escherichia coli (Van Vliet et al., 1984) and leads to suggestions about residues involved in substrate binding and catalysis. An analysis of levels of RNA in fetal and neonatal liver shows that ornithine transcarbamylase mRNA levels increase from about 40% of adult levels at day 14 of gestation to a peak at day 20 of gestation, and, after a drop around the time of birth, rises to adult levels during the second week after birth.
Collapse
|
47
|
Primary structure of the nuclear PUT2 gene involved in the mitochondrial pathway for proline utilization in Saccharomyces cerevisiae. Mol Cell Biol 1985. [PMID: 6098824 DOI: 10.1128/mcb.4.12.2837] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The PUT2 gene, believed to encode delta 1-pyrroline-5-carboxylate dehydrogenase, has been completely sequenced. The DNA contains an open reading frame of 1,725 base pairs encoding a protein of 575 amino acids. Transcript mapping with both S1 nuclease and primer extension methods revealed numerous initiation sites of RNA synthesis 50 to 80 base pairs downstream from several TATA boxes. The deduced amino acid sequence of delta 1-pyrroline-5-carboxylate dehydrogenase contains a highly basic amino terminus that may serve as the signal sequence that targets this protein to the mitochondrion.
Collapse
|
48
|
Rapid method for isolation and screening of cytochrome c oxidase-deficient mutants of Saccharomyces cerevisiae. J Bacteriol 1985; 161:831-5. [PMID: 2982789 PMCID: PMC214973 DOI: 10.1128/jb.161.3.831-835.1985] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
We describe here a new method for the specific isolation of cytochrome c oxidase-deficient mutants of Saccharomyces cerevisiae. One unique feature of the method is the use of tetramethyl-p-phenylenediamine as a cytochrome c oxidase activity stain for yeast colonies. The staining of yeast colonies by tetramethyl-p-phenylenediamine is dependent upon a functional cytochrome c oxidase and is unaffected by other lesions in respiration. Since the tetramethyl-p-phenylenediamine colony staining reaction is rapid and simple, it greatly facilitates both the identification and characterization of cytochrome c oxidase-deficient mutants. Another feature of the method, which is made possible by the tetramethyl-p-phenylenediamine colony stain, is the use of an op1 parent strain for the isolation of nuclear pet or mitochondrial mit mutants in specific protein-coding genes. A parent strain that carries this marker selects against rho0 or rho- classes of pleiotropic respiratory-deficient mutants, since these are lethal in op1 strains. We have used this method to isolate 123 independently derived cytochrome c oxidase-deficient pet mutants and 300 independently derived mit mutants.
Collapse
|
49
|
Reid GA. Chapter 7 Transport of Proteins into Mitochondria. ACTA ACUST UNITED AC 1985. [DOI: 10.1016/s0070-2161(08)60329-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
|
50
|
Garriga G, Lambowitz AM. RNA splicing in neurospora mitochondria: self-splicing of a mitochondrial intron in vitro. Cell 1984; 39:631-41. [PMID: 6096015 DOI: 10.1016/0092-8674(84)90470-7] [Citation(s) in RCA: 157] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
We have used Neurospora nuclear mutant cyt-18-1, which accumulates a number of unspliced mitochondrial precursor RNAs, to identify rapidly mitochondrial introns that are self-splicing in vitro. Incubation of deproteinized whole mitochondrial RNA from the mutant with 32P-GTP resulted in strong labeling of a 1.3 kb RNA, subsequently identified as cytochrome b (cob) intron 1, and weaker labeling of additional RNAs. Self-splicing of cob intron 1, including precise cleavage and ligation, was confirmed using an in vitro transcript synthesized from the SP6 promoter. The in vitro splicing reaction was shown to be analogous to that for the Tetrahymena nuclear rRNA intron. Since splicing of cob intron 1 is inhibited in a recessive nuclear mutant, we infer that this essentially RNA-catalyzed splicing reaction must be facilitated by a protein in vivo.
Collapse
|